# This file is NOT licensed under the GPLv3, which is the license for the rest
# of YouCompleteMe.
#
# Here's the license text for this file:
#
# This is free and unencumbered software released into the public domain.
#
# Anyone is free to copy, modify, publish, use, compile, sell, or
# distribute this software, either in source code form or as a compiled
# binary, for any purpose, commercial or non-commercial, and by any
# means.
#
# In jurisdictions that recognize copyright laws, the author or authors
# of this software dedicate any and all copyright interest in the
# software to the public domain. We make this dedication for the benefit
# of the public at large and to the detriment of our heirs and
# successors. We intend this dedication to be an overt act of
# relinquishment in perpetuity of all present and future rights to this
# software under copyright law.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
#
# For more information, please refer to <http://unlicense.org/>

from distutils.sysconfig import get_python_inc
import platform
import os
import ycm_core

# These are the compilation flags that will be used in case there's no
# compilation database set (by default, one is not set).
# CHANGE THIS LIST OF FLAGS. YES, THIS IS THE DROID YOU HAVE BEEN LOOKING FOR.
flags = [
    '-Wall',
    '-Wextra',
    '-Werror',
    '-Wno-long-long',
    '-Wno-variadic-macros',
    '-fexceptions',
    '-DNDEBUG',
    # You 100% do NOT need -DUSE_CLANG_COMPLETER and/or -DYCM_EXPORT in your flags;
    # only the YCM source code needs it.
    '-DUSE_CLANG_COMPLETER',
    '-DYCM_EXPORT=',
    # THIS IS IMPORTANT! Without the '-x' flag, Clang won't know which language to
    # use when compiling headers. So it will guess. Badly. So C++ headers will be
    # compiled as C headers. You don't want that so ALWAYS specify the '-x' flag.
    # For a C project, you would set this to 'c' instead of 'c++'.
    '-x',
    'c',
    '-isystem',
    get_python_inc(),
    '-isystem',
    '/usr/include',
]

# Clang automatically sets the '-std=' flag to 'c++14' for MSVC 2015 or later,
# which is required for compiling the standard library, and to 'c++11' for older
# versions.
if platform.system() != 'Windows':
  flags.append( '-std=c++11' )


# Set this to the absolute path to the folder (NOT the file!) containing the
# compile_commands.json file to use that instead of 'flags'. See here for
# more details: http://clang.llvm.org/docs/JSONCompilationDatabase.html
#
# You can get CMake to generate this file for you by adding:
#   set( CMAKE_EXPORT_COMPILE_COMMANDS 1 )
# to your CMakeLists.txt file.
#
# Most projects will NOT need to set this to anything; you can just change the
# 'flags' list of compilation flags. Notice that YCM itself uses that approach.
compilation_database_folder = ''

if os.path.exists( compilation_database_folder ):
  database = ycm_core.CompilationDatabase( compilation_database_folder )
else:
  database = None

SOURCE_EXTENSIONS = [ '.cpp', '.cxx', '.cc', '.c', '.m', '.mm' ]

def DirectoryOfThisScript():
  return os.path.dirname( os.path.abspath( __file__ ) )


def IsHeaderFile( filename ):
  extension = os.path.splitext( filename )[ 1 ]
  return extension in [ '.h', '.hxx', '.hpp', '.hh' ]


def FindCorrespondingSourceFile( filename ):
  if IsHeaderFile( filename ):
    basename = os.path.splitext( filename )[ 0 ]
    for extension in SOURCE_EXTENSIONS:
      replacement_file = basename + extension
      if os.path.exists( replacement_file ):
        return replacement_file
  return filename


def FlagsForFile( filename, **kwargs ):
  # If the file is a header, try to find the corresponding source file and
  # retrieve its flags from the compilation database if using one. This is
  # necessary since compilation databases don't have entries for header files.
  # In addition, use this source file as the translation unit. This makes it
  # possible to jump from a declaration in the header file to its definition in
  # the corresponding source file.
  filename = FindCorrespondingSourceFile( filename )

  if not database:
    return {
      'flags': flags,
      'include_paths_relative_to_dir': DirectoryOfThisScript(),
      'override_filename': filename
    }

  compilation_info = database.GetCompilationInfoForFile( filename )
  if not compilation_info.compiler_flags_:
    return None

  # Bear in mind that compilation_info.compiler_flags_ does NOT return a
  # python list, but a "list-like" StringVec object.
  final_flags = list( compilation_info.compiler_flags_ )

  # NOTE: This is just for YouCompleteMe; it's highly likely that your project
  # does NOT need to remove the stdlib flag. DO NOT USE THIS IN YOUR
  # ycm_extra_conf IF YOU'RE NOT 100% SURE YOU NEED IT.
  try:
    final_flags.remove( '-stdlib=libc++' )
  except ValueError:
    pass

  return {
    'flags': final_flags,
    'include_paths_relative_to_dir': compilation_info.compiler_working_dir_,
    'override_filename': filename
  }
